DefinePK

Abstract

The study was aimed to provide the basic findings about the histochemical and immunohistochemical details of bursa of Fabricius in Nandanam broiler chickens of four different age groups viz., day-old, two, four and six weeks. Paraffin sections and cryosections of fresh unfixed tissue, tissues fixed in chilled formol-calcium and neutral buffered formaldehyde were used for various histochemical and immunohistochemical studies. The presence of acid and neutral mucopolysaccharides was demonstrated in the epithelial cells lining the bursal mucosa, tunica serosa and epithelium between the cortex and medulla of lymphoid follicles. The presence of tyrosine kinase (Trk) like protein was evident in the epithelium lining the bursal plicae and lymphoid follicles in all the age groups studied. Lipid droplets were noticed only in interfollicular connective tissue in day-old birds. They were also noticed in the cortex and medulla of lymphoid follicle from two weeks onwards and they coalesced to form clumps in the medulla as age advanced. Metachromasia in the epithelium covering the bursal plicae, in mast cells present in the interfollicular connective tissue and in subcapsular area was demonstrated by toluidine blue method. The Bu-1a+ cells were found both in the cortex and medulla, but the intensity of immune-labelling was more in cortex when compared to medulla. CD3+ cells were noticed in the bursa of all age groups except day-old birds.